Field
Embodiments of the invention relate to semiconductor processing and, in particular, to plasma etching.
Description of the Related Art
Plasma etching processes can be used to form vias and other structures on a substrate. For example, a plasma etching process can be used for etching wafers in heterojunction bipolar transistor (HBT) or bipolar field effect transistor (BiFET) GaAs processes.
The processing time of a wafer in a plasma etcher can be important for throughput of a fabrication facility. Thus, it can be desirable to complete a plasma etching process in a relatively short time. Furthermore, it can be desirable to reduce the frequency of maintenance and repair of a plasma etcher, in order to improve throughput and to reduce costs.
Accordingly, there is a need for improved methods of etching wafer features and for improved plasma etchers.